Electric contact device, preferably for relays



Jan. 12, 1954 H. KUHNKE ELECTRIC CONTACT DEVICE, PREFERABLY FOR RELAYS Filed June 15, 1950 IN V EN TOR.

HELLMUTH KUHNKE.

Patented Jan. 12, 1954 ELECTRIC CONTACT DEVICE, PREFERABLY FOR RELAYS Hellmuth Kuhnke, Malente-Gremsmuhlen, Germany Application June 15, 1950, Serial No. 168,191

Claims priority, application Germany December 1, 1949 2 Claims. (01. 200-404) l My invention relates to electric contact devices for relays and other contactors and particularly toga contact spring assembly for such contactors.

The desire to give relays and like contact devices with multiple contacts a design of minimum space requirements has led to the choice of an exterior shape and size closely adapted to the cylindrical shape of the relay control coil. Such a design has also the advantage that it facilitates providing the base of the device with contact pins for plugging it into a socket in the manner of an amplifier tube. However, in the known relay designs, though the relay housing may be cylindrical, the assembly of the contact springs has a non-cylindrical overall shape so that the space available within the housing is only poorly utilized.

It is an object of my invention to provide a contact device for relays and other contactors, Whose space requirements for a given length of the contact springs are considerably smaller than those of comparable known assemblies. More particularly, it is an object of the invention to provide a contact device or spring assembly of generally cylindrical overall shape whose axial height depends only upon the number of the contacts to be actuated and whose diameter is substantially determined by that of the appertaining relay control coil. Another object, akin to the foregoing, is to provide a relay in which the space within a cylindrical housing is virtually fully utilized and contains contact springs of larger effective length than those heretofore accommodated in relay housings of the same size.

To achieve these objects, and in accordance with my invention, I mount a plurality of partcircular or similarly arcuate contact springs in a common plane substantially perpendicular to the direction of contact actuation, one or several planes or levels of such spring groups being provided to form a set or assembly. According to another feature of the invention, the contact springs are actuated by a rod axially disposed and axially displaceable within the circular or cylindrical space surrounded by the arcuate springs, the rod being equipped with actuating members engageable with the springs for flexing them perpendicularly to the above-mentioned plane to thereby move the contact points of the springs into or out of engagement with corresponding stationary contacts. According to another feature, the movable contact springs and the likewise spring-like stationary contacts are K 2 stacked upon one another with alternately inserted pieces of insulating material to form a set or unit, and the contact springs are designed so that only the movable springs are entrained by the actuating members.

These and other features of my invention are apparent from the embodiment illustrated on the drawing, in which Figure 1 shows a part-sectional view of an electromagnetic relay with a contact device according to the invention, the section being taken along the plane indicated in Fig. 2 by I-I; and

Fig. 2 is a top view of the same relay, the appertaining housing being shown in cross section.

The illustrated electromagnetic relay has a control coil I mounted on the core 5 of a magnet structure composed of yokes 2 and 3. The appertaining armature 4 is connected with a pusher rod 6 which extends upwardly and axially through a bore of core 5 and carries insulating actuating members I, 8 and 9. When coil is excited, the armature 4 is attracted toward core 5 and lifts the rod 6 so that members 1, 8, 9 actuate the movable contact springs ID to IE by engaging respective nose IE or IT. Then the movable contact springs in to 15 are separated from respective lower stationary contact springs 2 G to 25, and placed into engagement with upper stationary contact springs such as those denoted by 30, 3! and 32. The stationary contact springs do not have the projecting noses l6, ll of the movable springs but are otherwise of similar arcuate shape. The various movable and stationary contact springs are stacked together with intermediate spacers of insulating material such as those denoted by 36, 37, 38. Each of the two stacks of the illustrated embodiment is held together and rigidly secured to yoke 3 by means of a screw bolt 39. The number and arrangement of the movable and stationary contact springs may be varied to suit the requirements of each particular application. The magnet structure of the relay may be mounted on an insulating base with connecting plugs similar to the plug-type bases used for electronic tubes.

A cup-shaped housing it covers the relay. It will be recognized that its interior cylindrical space is almost fully utilized by the magnet and the contact assembly. Preferably and as shown, the exterior diameter of the set of contact springs is substantially equal to the diameter of the electromagnet to secure optimum space utilization at an optimum elastic length of the individual springs.

Devices according to the invention are not limited to electromagnetic relays but are applicable in contactors for different actuation, for instance, manually operable switches.

I claim:

1. An electric contact device, comprising an electromagnet having a magnetizable core structure and a cylindrical coil concentrically disposed on said structure and having an axial center bore, said magnet having an axially movable armature member disposed at one axial side of said coil, an axially displaceable pusher rod joined with said armature and extending through said bore to the opposite side of said coil, a stack of axially aligned sets of contact springs insulated from each other and disposed on said core structure at said opposite coil side, each of said sets having two substantially flat springs of arcuate shape arranged substantially on a circle about said rod and in a common plane perpendicular to the rod axis, each spring being at one end rigidly mounted on said core structure and'being movable at the other end, and each of said sets having. in said plane an outer diameter substantially equal to the diameter of said electromagnet, mu-

4 tually insulated stationary contact members also mounted on said core structure and engageable with the respective other ends of said respective springs, said rod having axially spaced parts engageable with said springs for vmoving said springs relative to said stationary contact members when said rod is displaced by movement of said armature, whereby the overall space oocupied by the device is minimized.

2. In a contact device according to claim 1, each of said contact springs having at said other end a radially and inwardly projecting nose engageable by one of said pusher-rod parts.

HELLMUTH KUI-INKE.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,172,397 Meuer Sept. 12, 1939 2,259,183 Snavely Oct. 14, 1941 2,266,536 Cooper Dec. 16, 1941 2,379,772 Wellman July 3, 1945 2,451,810 Cohen Oct. 19, 1948 

